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121.
Jun Wang Shengli Li Yi Zhao Juan Shi Lili Lv Huazhi Wang Zhiya Zhang Wangjun Feng 《RSC advances》2018,8(12):6660
With a high specific capacity (4200 mA h g−1), silicon based materials have become the most promising anode materials in lithium-ions batteries. However, the large volume expansion makes the capacity reduce rapidly. In this work, a periodic silicon/carbon (Si/C) multilayer thin film was synthesized by magnetron sputtering method on copper foil. The titanium (Ti) film (about 20 nm) as the transition layer was deposited on the copper foil prior to the deposition of the multilayer film. Superior electrochemical lithium storage performance was obtained by the multilayer thin film. The initial discharge and charge specific capacity of the Si (15 nm)/C (5 nm) multilayer film anode are 2640 mA h g−1 and 2560 mA h g−1 with an initial coulombic efficiency of ∼97%. The retention specific capacity is about 2300 mA h g−1 and there is ∼87% capacity retention after 200 cycles.With a high specific capacity (4200 mA h g−1), silicon based materials have become the most promising anode materials in lithium-ions batteries. 相似文献
122.
To solve the problem of contamination of hexavalent chromium (Cr(vi)), visible-light-driven graphene-based ternary metal chalcogenide nanosheets (rGO/SnIn4S8) were synthesized via a one-pot surfactant-assisted hydrothermal method for the photoreduction of Cr(vi). Characterizations demonstrated that SnIn4S8 nanosheets were uniformly distributed on the surface of rGO and the as-synthesized nanosheets exhibited excellent photocatalytic activity under visible light. In addition, the effects of pH, concentration of critic acid, holes and electron scavengers on the reduction of Cr(vi) were systematically investigated. It was found that 50 mg L−1 of Cr(vi) could be completely removed within 30 min at pH 2 when citric acid served as a hole scavenger. Kinetic studies showed that the photocatalytic reduction of Cr(vi) processes obeyed the pseudo first order model. Further study indicated that the Cr(iii) species was immediately adsorbed onto the surface of the rGO/SnIn4S8 nanosheets after photocatalytic reduction of Cr(vi). Additionally, recycling results suggested that rGO/SnIn4S8 nanosheets possessed high recycle ability and stability after repeated use (5 times). This effective and promising work might provide a new strategy for the photoreduction of Cr(vi) and complete removal of chromium from effluent through the novel photocatalyst rGO/SnIn4S8.Fabrication of visible-light-responsive photocatalyst (rGO/SnIn4S8) for photoreduction of Cr(vi) and adsorption of Cr(iii). 相似文献
123.
The pathophysiology of delayed cerebral vasospasm (CVS) after subarachnoid haemorrhage (SAH) is multifaceted and involves endothelial apoptosis and inflammation. Ethyl pyruvate (EP) could attenuate early brain injury following SAH via anti-inflammation and inhibition of the c-Jun N-terminal kinase (JNK) signalling pathway. However, the role of EP in the delayed CVS has yet to be determined. In this study, we examined the effect of EP on endothelial apoptosis and inflammation and explore possible signalling pathways. We found that EP could significantly attenuate the delayed CVS. Possible mechanisms include a decrease in the endothelial cell apoptosis of the basilar artery and alleviation of endothelial inflammation. The JNK signalling pathway may play an important role in the neuroprotective effects of EP on delayed CVS. The results suggest that EP may be a possible therapy for delayed CVS, and the JNK signalling pathway should be targeted for therapeutic purposes in the future.The pathophysiology of delayed cerebral vasospasm (CVS) after subarachnoid haemorrhage (SAH) is multifaceted and involves endothelial apoptosis and inflammation. 相似文献
124.
Xinji Gong Yuehua Li Jing Wang Gang Wu Ayinuer Mohemaiti Qimanguli Wushouer Lidan Yao Jianghua Lv Rongrong Li Pengfei Li Buqing Wang 《RSC advances》2018,8(16):8983
Background: Despite great effort to control tuberculosis (TB), low treatment adherence threatens the success of drug therapy, increases the risk of TB transmission, and leads to the development of drug resistance. The present study assessed anti-TB treatment adherence in sputum smear-positive TB patients and examined the risk factors for poor patient adherence to identify targets for intervention. Methods: We monitored and followed up TB patients who were diagnosed between July 2014 and June 2015 in Xinjiang, China. A total of 8289 sputum smear-positive TB patients were included in this study. All patients registered their information during the first hospital visit or with the Centers for Disease Control, had regular follow-up visits, and accepted the anti-TB treatment. Insufficient re-examination adherence was defined as undergoing fewer than the recommended three sputum smear examinations during the treatment course. Results: Among 8289 patients, 3827 men (84.4% of male patients) and 3220 women (85.7% of female patients) had good adherence during treatment follow-up. 1242 patients (15.0%) did not complete regular follow-up. 332 (4.0%) patients lost contact. An adjusted logistic regression model showed that ethnicity, household address, treatment classification, patient source, and the actual management were significantly associated with non-adherence. Conclusion: The Xinjiang TB epidemic situation remains grim. Smear-positive patients had a higher proportion of non-adherence, which increased treatment difficulties and the risk of death from TB. Relevant medical departments should strengthen their supervision and interventions during the TB treatment process to improve patient adherence to anti-TB treatment.Background: Despite great effort to control tuberculosis (TB), low treatment adherence threatens the success of drug therapy, increases the risk of TB transmission, and leads to the development of drug resistance. 相似文献
125.
Xiuzhen Wei Xiaoyan Bao Jiawei Wu Cuixia Li Yingying Shi Jinyuan Chen Bosheng Lv Baoku Zhu 《RSC advances》2018,8(19):10396
The rejection behaviors of two different charged composite hollow fiber nanofiltration (NF) membranes for six pharmaceutical molecules, primidone, carbamazepine, sulfamethoxazole, atenolol, sulfadimidine and norfloxacin, were characterized in this study. The saturation adsorption behaviors of the different pharmaceutical molecules on each membrane surface were studied and found to be related to the molecular weight, charge and hydrophilicity of the pharmaceutical molecules. After the pharmaceutical molecules reached adsorption equilibrium, the rejection rates of different NF membranes were characterized. The rejection rates of primidone, carbamazepine, sulfamethoxazole, atenolol, sulfadimidine and norfloxacin by the PEI-NF membrane were 85.6%, 91.8%, 79.9%, 98.1%, 93.3%, and 97.1%, respectively. Meanwhile, the rejection rates of the pharmaceutical molecules by the PIP-NF membrane were 82.2%, 85.4%, 91.5%, 79.1%, 87% and 93.3%, respectively. The influence of feed concentration, operation pressure, temperature, pH and ionic strength on the rejection behaviors of the different charged NF membranes were also studied.The rejection behaviors of two different charged composite hollow fiber nanofiltration (NF) membranes for six pharmaceutical molecules, primidone, carbamazepine, sulfamethoxazole, atenolol, sulfadimidine and norfloxacin, were characterized in this study. 相似文献
126.
Purpose
Contrast-enhanced ultrasound (CEUS) can distinguish between central lung cancer and atelectatic lung tissue. The aim of this study was to explore the clinical value of CEUS for biopsy in patients with central lung cancer with obstructive atelectasis.Methods
One hundred and twelve patients were selected and CEUS was performed to display central lung cancer and atelectatic lung tissue. The front edge of central lung cancer was punctured with a needle, avoiding the necrotic area, under the guidance of CEUS.Results
All of the 112 lesions were diagnosed with a clear central lung cancer mass and atelectatic lung tissue. In 104 cases, the central lung cancer mass presented with a “slow-in and fast-out” pattern compared to atelectatic lung tissue. In eight cases, the central lung cancer mass presented with a “fast-in and fast-out” pattern compared to atelectatic lung tissue. The mean number of punctures was 2.6, and the success rate of puncture biopsy was 98%. Of the 112 patients, six cases had hemoptysis during the procedure and 10 patients had bloody sputum in the postoperative period. No complications were found in the other cases.Conclusion
CEUS has important clinical value for needle biopsy of central lung cancer with atelectasis.127.
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129.
Mengci He Fanpeng Kong Geping Yin Zhe Lv Xiudong Sun Hongyan Shi Bo Gao 《RSC advances》2018,8(26):14369
Molybdenum disulfide (MoS2) is a promising electrocatalyst for hydrogen evolution reaction (HER), but only edges and S-vacancies are catalytic active sites for the HER. Therefore, it is crucial to increase edge sites and S-vacancies for enhancing the HER activity of MoS2. Here, we report an enhanced HER activity of MoS2 by combing vertical nanosheets and H2 annealing. Compared to horizontal MoS2 nanosheets, pristine vertical MoS2 nanosheets showed better HER activity due to a larger amount of edges. H2 annealing further enhanced the HER activity of vertical MoS2 nanosheets remarkably. Scanning electron microscopy (SEM), X-ray photoelectron spectra (XPS) and electrochemical impedance spectroscopy (EIS) were used to elucidate the enhanced HER activity by H2 annealing. SEM images showed that H2 annealing roughened the MoS2 edges, leading to more edge sites. XPS data revealed the smaller S : Mo ratio after H2 annealing, meaning more S-vacancies. Meanwhile, EIS measurements showed that charge transfer was accelerated by H2 annealing. These findings elaborated the H2 annealing induced enhancement of the HER activity, which were further confirmed by the subsequent re-sulfurization experiment.Vertical configuration and H2 annealing enhanced the hydrogen evolution reaction activity of MoS2 nanosheets. 相似文献
130.
Jun Lv Canqing Yu Yu Guo Zheng Bian Sarah Lewington Huiyan Zhou Yunlong Tan Junshi Chen Zhengming Chen Liming Li 《Journal of epidemiology / Japan Epidemiological Association》2015,25(3):221-230